Fun with the new Porsche plus some tech

[grimesb]

Hello Everyone,

I've finally done it! I picked up a 2001 Base Boxter in pretty good condition with 85k miles. Thank you everyone for answering all of my questions on these forms and for being so helpful as to even offer to speak with me over the phone pre-purchase.

Seriously, any of you folks come to Austin, Texas and I'll buy the beers.

I've been getting acquainted with the car and so far have done oil, transmission fluid, coolant, fuel filter, and serpentine belt. It's been pretty fun as this was my first car purchase, first car I've worked on, and first standard transmission I've ever driven.


* For the technical bit*

As of 08/13/2012 I'm now looking at some more extensive issues that I'd like your opinion on. I've got my first CEL and I'm pulling a P1128 and P1130. To my understanding the car computer tells the fuel system its lean but in reality its very rich. I say this because I've eaten a quarter tank of gas in 20-so miles.

1. AOS was replaced with new MAF at the end of June by the previous owner and the mechanic pulled the P1130 but not the P1128. I bought the car a day or two after it was replaced.
2. Idle is a pretty steady 750rpm
3. The car operates at about 180-200 degrees
4. After a few drives I noticed a 2-3 ounce puddle of coolant once I park the car. If it sits for a few days it does not continue, it simply lets this out after a drive to operating temperature.
5. I've noticed a drop of oil at park and I lost a digital bar on the oil gauge over the last month. I'm optimistic that its simply the higher viscosity oil causing this.

I took the car to a local mechanic and he's stating I need to reseal my valve cover gaskets and replace the coolant tank in the trunk. The tune is about 2k worth of work. Plus 300 for spark plugs but I feel I can take that on myself.

I asked his opinion on if it could be from the oil filler tube and or possibly old spark plug o-rings and he's not considering it. He states he smoke tested the car and saw the seepage.

A few additional points:

1. On one drive before the CEL and one after I got a moderate white puff of smoke from the engine compartment at 80-85mph from the passenger exhaust.
2. I attributed a burning smell I got after car to car traffic for longer periods of time due to me learning on this clutch and burning it a bit in the process. It comes from the passenger side exhaust area.


I was thinking I would clean the engine, replace spark plugs, and pay for the oil filler tube to be replaced. Wait, watch, and see what happens? Suggestions would be greatly appreciated.

I plan on replacing the coolant tank soon but would like to get a bit more familiar with the car and try to do it myself.

Thanks,

Bennett

[The Radium King]

ok.

coolant tank is a failure item on the boxster and could be the reason for your coolant puddle. note also, however, that the coolant tank cap has been updated as the old one would leak under pressure. perhaps you need a new cap only.

it is much more likely that you have a cracked spark plug tube or failed spark plug tube o-ring than a cam cover that needs resealing. do your plugs/tubes and retorque the cam cover fasteners. if the leak continues then redo your cam covers. there's a dyi here and is possible with the engine in the car (apprarently; haven't done it myself but there looks to be enough room in there).

your code is the car trying to get sufficient fuel into the air/fuel mixture. it is running full rich (calling for as much gas as the ecu will allow) but the o2 sensors post-combustion are saying that there is not enough gas. so, problem with fuel delivery, 02 sensors or maf. if was only happening on one bank i would say bad injector or 02 sensor, but since it is happening on both it is maf or perhaps a vacuum leak (air getting into the system that the maf doesn't see). one source of vacuum leak is a cracked oil fill tube allowing air in past the aos. so, disconnect your maf; the computer will resort to the throttle position sensor to determine amount of air into the system. if your car runs ok then the problem is maf or vacuum leak pre-throttle body (oil fill tube, or perhaps aos - *** edit to address my f-up; aos enters after tb ***). if it continues to run rough then your problem is 02 sensor, vacuum leak post-throttle body or possibly bad injectors. sniff your oil - does it smell like gas? if so then an injector or two might be stuck partially open (happened to me) - leaking gas into the oil when the car sits, but won't open enough to get proper air/fuel mix and resulting in a lean condition when computer calls for full rich.

[UNYboater]

Originally Posted by grimesb

Hello Everyone,

I've finally done it! I picked up a 2001 Base Boxter in pretty good condition with 85k miles.
It's been pretty fun as this was my first car purchase, first car I've worked on, and first standard transmission I've ever driven.

First of all, congratulations !!! That's a pretty good trifecta!
Second, could the smell be oil instead of clutch-wear? While moving, that same small oil drip that ends up on the ground could end up on the hot manifold while moving slowly. If it were the clutch, it's a distinctly different smell.

Good luck! And keep us posted.

[grimesb]

Thanks for the replies!

Quick question:

1. When you say continue to "run rough" are you referring to the large amount of gas being used? Or is it just a general term used for running incorrectly? Because from my student-perspective the car runs pretty well minus the oil leak and very poor fuel economy. It hasn't had any rough patches/idle issues/misfires that I know of and if you were to get into the car today you'd only notice the CE light and oil drip after operating temp has been reached.

I'm still trying to learn how each part of the car connects to the other and I'm only starting to understand the basics of the MAF's / O2 sensors trail. I'm most likely just having issues conceptually grasping the flow of things.

Question about the cam cover re-torquing: Can I give them a quarter turn tightening or for safety purposes do they need to be taken off and 100% re-torqued? Also, any suggestions on what I can read ( hopefully with pictures ) to better understand where the cam covers are and laymans for what they do. Most articles I've searched are more on the higher technical side.

Thanks,

Bennett

[The Radium King]

'run rough' - i meant throwing the codes.

how the car works - you push gas pedal and open throttle body valve. air rushes in past mass air flow sensor. sensor can sense density, volume, etc. takes quantity of air and references to a map in the computer (different maps for different rpm, engine load, etc.) and computer determines a quantity of fuel to deliver. information sent to injectors, injectors release fuel, boom goes the dynamite and exhaust gasses flow past the the o2 sensor on their way out the back. o2 sensor looks at the amount of uncombusted oxygen in the exhaust and tells the computer which then revises the amount of fuel delivered. with the codes you are getting the 02 sensors are seeing too much uncombusted o2 in the exhaust (a lean condition - not enough fuel) so the comuputer is calling for more gas from the injectors. even at max gas (full rich) the o2 is not fully combusting so computer throws a code. so, either you have a bad maf that is telling the computer that it is getting less air than it really is, or there is a vacuum leak letting air in after the maf, or the 02 sensors are sending faulty readings, or there is something causing insufficient fuel (bad injector, bad fuel pump, bad fuel pressure regulator). typically a bad pump will show up as an intermittent issue or under high load situations, while a bad fpr will act up in high load situations.

disconnecting the maf takes it out of the equation, as the computer then defaults to the throttle position to estimate the amount of air going it. this also takes any vacuum leaks from upstream of the the throttle body out of the equation (but not downstream, noting that the aos - a potential source of vacuum leaks - enters the system after the throttle body).

cam covers - look here: Pelican Technical Article: Boxster Camshaft Upgrade / Chain Tensioner Replacement - 986 / 987

specifically figure 26.

[grimesb]

Update:

Cleaned up MAF sensor and put it back in.

Now I'm working cleaning the underside and getting the spark plugs done.